2023-01-17

70 MHz Home Made Equipment

One of the exciting things about the 70 MHz band is that you have to build most of the equipment yourself. Below you can find several things that I am using and have developed together with other radio amateurs who also enjoy 70 MHz.

These webpages will help you to get active on 70 MHz whether you already have access to 70 MHz, perhaps think you might get it one day or want to work crossband to either 50 MHz or 144 MHz.

Equipment

Equipment	Description (click on flag to read)		Kits
Transverter			Not available
25 W power amplifier			Not available
Low pass filter	-		Not available
½ λ vertical		-	Not available

Kit alignment support

Below is a list of people who on a voluntary basis would like to help you align your 70 MHz kits if you do not have the tools needed. Find one near you and send him an e-mail to find out if he can help you. Please keep in mind that these persons do it on a voluntary basis!

Testimonials

Alastair, GM3NGK

Pleased to advise you that the transverter is now complete, the photo was taken following sweeping the filters but prior to final soldering work including the installation of both mixers.

Last night Mark, GM4ISM, put the transverter on his spectrum analyzer for the final alignment. Mark is very particular and following completion of the alignment and additional testing he was really impressed with its performance.

Yes I enjoyed assembling the transverter and grateful for Mark's time and experience to do the alignment.

Graham, G3TCT

Just to say that I have now completed my transverter and PA, both to your design, and all working ok. I can get 35 W out for 81 W in, which is 43% efficiency.

I have measured the IMD at about -28 dB at 20 W PEP output, but this is the same as the 28 MHz rig driving it! So it is very close to your measured value.

I attach photos of my version in case this is useful to others. I found the photos of other builds on your website very useful. I wanted to see how hot the PA module got, so I have glued a temperature sensor to it (LM35). The sensor is now glued to the copper on the output side of the PA, not to the case as shown in the photo. The output feeds the meter directly through 820 Ω.

Mark, CT1FJC

I very much enjoyed building this kit and it is working well. This is a nice piece of work and builds beautifully. Congratulations to all concerned. The 90 micron spacer was very welcome. I have had 35 W into a dummy load from it, but have turned it down because of the power restrictions in CT.

Michael, OH2AUE

The OZ transverter kit in itself is recommendable; the RF performance is very good, especially with the PA module. Some experience is needed in assembly and it is always wise to check your handywork with some test equipment at your local club or like here in Finland at the annual VHF meeting test lab.

Peter, PA2V

Peter's, PA2V, article in Dutch Elektron.

Verner, OZ5TG

Bare denne besked - sjældent har man set et mere komplet og perfekt byggesæt.

Ingen mangler - ingen problemer - tuner problemfrit op både sender og modtager. I begyndelsen manglede jeg 20 dB på modtageren, men det hjalp da J310 blev monteret på 28 MHz!

Genhør på 70 MHz. Nu kan min gamle converter (der svinger lystigt ind imellem) komme på pension.

Users' links

Feel free to add a review on eHam.

Bo, OZ2M, www.rudius.net/oz2m